High-spirited residents of the Central Kalimantan capital of Palangkaraya gathered on soccer fields to take part in games and competitions to celebrate Indonesia's 61st Independence Day on Aug. 17.

But something was bothering them: thick smog from forest fires, which had blanketed much of the province since the end of June.

Visibility in the city was 50 to 100 meters in the morning, and only a little better in the afternoon.

"It's actually better than last year, when we were forced to wear masks wherever and whenever we ventured out," said Andreas Dody Permana, a Palangkaraya civil servant.

"But this is just the beginning. Dry season will not end until the end of the year. So the worst is yet to come."

The annual forest fires have arrived again in many parts of Borneo and Sumatra, where 500 to 1,000 fire "hot spots" have sprung up, producing choking smoke that has spilled over to neighboring Malaysia, Singapore, Thailand and Brunei.

The smoke poses health threats and disrupts air and land transportation.

Leaders of the affected neighboring countries have expressed concern over the haze, with the latest protest coming from Malaysia's Deputy Prime Minister, Datuk Seri Najib Razak.

He told the New Straits Times that Indonesia's perennial environmental problem would not have recurred if the Indonesian government had taken action.

"As far as we are concerned, there is not much we can do about the Indonesian fires. Our ability to resolve the problem will largely depend on the determination of the Indonesian government to address the matter. This will be our major challenge," he said.

On April 22, President Susilo Bambang Yudhoyono ordered Forestry Minister M.S. Kaban and State Minister for the Environment Rachmat Witoelar, as well as leaders of regional administrations, to do their best to prevent forest fires.

"I don't want to see smog from forest fires in July, August and September," he said during the commemoration of International Earth Day in Jakarta.

The president faces fallout not only from the damage to the country's remaining 130 million hectares of forestland, but also from the embarrassment he endures every time he meets with other ASEAN leaders.

"The president doesn't know the actual conditions in the field ... It's impossible to completely stop the fires," said Afrudin, an entrepreneur, who fears prolonged haze will push his business into bankruptcy.

In Sumatra, forest fires began in July, sending haze as far as Malaysia, Singapore and Thailand.

About two weeks later, an increasing number of fire "hot spots" appeared in Kalimantan and the Malaysian states of Sarawak and Sabah in northern Borneo.

Satellite images show that Riau and West Kalimantan provinces recorded most of the hot spots.

World Wide Fund for Nature (WWF) Indonesia's data shows from the first week of July through the second week of August, more than 3,500 hot spots were detected in Riau, and some 4,000 in West Kalimantan.

Hot spots indicate that the area is generating heat at a level high enough to trigger satellite sensors. Not all hot spots are fires, however.

Just who is starting the fires is a matter of dispute. Officials from both the Forestry Ministry and the State Ministry for the Environment point to nomad farmers as the usual suspects.

"Most of the fires occur on private land. They are initiated by farmers clearing land by burning wood," said Triwibowo, the Forestry Ministry's director general for forest fire control.

Foresters and agricultural experts believe that during dry seasons farmers prepare for the planting season and opt for the cheapest way available to clear land: burning.

Shifting to a more environmentally-friendly method is not easy, environmentalists say.

"They (the farmers) also believe it could increase the soil fertility, a wisdom they pass from generation to generation," said Dedi Hariri, WWF's Forest Fires Monitoring Officer.

The ancient agricultural technique is not the only reason the fires spread over such a wide area. Most of the fires take place in peatland that burns easily when it is dry, allowing the fire to spread underground.

Peatland is composed of layers of dead organic matter. It is highly flammable and will produce higher smoke and carbon emissions than fires on other types of soil.

"Once burning, it is very difficult to extinguish," says Zulfahmi, coordinator of Forest Rescue Network Riau.

"The best way to prevent forest fires would be to stop granting licenses for land clearing on peatlands and by conserving the areas," he said.

Indonesia has the largest peatland area in Southeast Asia, with 20 million of the 30 million hectares across the region. The peat is found mostly in Sumatra, Kalimantan and Papua.

The official data shows that about two million hectares of peat soils in Sumatra and one million hectares in the Indonesian part of Borneo are severely damaged and fire-prone.

WWF Indonesia's data shows that over the last two years, more than half of the fires in Riau province have occurred in peatlands. In West Kalimantan, one fifth of the burned land was peat.

The Central Kalimantan chapter of the Indonesian Forum for the Environment (Walhi), however, believes land burning by farmers is not the main cause of the fires.

"Our investigation found that several oil palm plantations deliberately started fires," said the group's director, Satriardi.

"The government and the local administrations should focus on going after these bad companies rather than arresting nomadic farmers who cause relatively minor damage," he concluded.

Walhi has been investigating a fire allegedly started by employees of a Malaysian oil palm company operating in Seruyan Regency, Central Kalimantan.

"I doubt the police and provincial administration will follow up our findings," he said.

On paper, the government has imposed a no-burning policy for land and forest conversion. The 1997 Environment Law, the 1999 Forestry Law and the 2004 Plantation Law clearly stipulate that those who burn land or forests for land-clearing purposes are subject to 15 years imprisonment and a Rp 750 million (US$82,217) fine.

Several provincial and municipal administrations in Sumatra and Kalimantan have also issued regulations banning farmers from burning land and forests, unless they obtain a license to carry out "limited and controlled fires" on their own properties.

But weak law enforcement combined with messy coordination between government institutions and the police render the regulations toothless.

"Since the massive fires in 1997, nobody has been arrested. I guess the government, the provincial and municipal administrations have problems enforcing the law," said Sri Rahayu, head of the Central Kalimantan Environmental Management Agency's pollution control division.

"We have to catch the perpetrators red handed. But so far, we have no evidence that the landowners or companies have deliberately set their land on fire," she said.

In 1997, massive forest fires ravaged 10 million hectares of lands and forests across the country, leaving much of Southeast Asia blanketed with choking haze for days and affecting the health of some 70 million people across the region.

Satriardi said the issue of law enforcement was not as delicate as state officials believed, adding that "it's just a matter of political will."

He believed regional administrations across Borneo hesitated to hunt down the perpetrators because most of the land was owned by local politicians or tycoons.

Yohannes of the Central Kalimantan Natural Resource Conservation Office agreed some businesses may be involved in burning forests. He noted that fires erupt annually in concessions belonging to plantation firms, industrial timber estate and logging firms.

But arresting is not his office's task because BKSDA was established to protect and monitor the management of conservation areas.

"Our authority is to arrest the perpetrators of fires that occur in conservation areas. But at present, all the fires occur on private land, so it's not our mandate to enforce the law in such areas," said Yohannes.